Artificial limb



Oct, 22, 1929- E, ELEVENS 1,732,220 V ARTIFICIAL LIMB Filed Aug; 16, 1927 gwtnntoz E'mm eff Bleverzs Patented Oct. 22, 1929 I STATES EMMETT BLEVENS, LOUISVILLE, KENTUCKY ARTIFICIAL LIMB Application filed August 16, 1927.

T his invention relates to artificial limbs of that type comprising upper and lower leg sections pivotally united by a knee joint and in which means, including shoulder straps or suspenders, are employed for permitting and controlling the bending and straightening of the leg whereby a correct action for walking is obtained.

In such limbs, as heretofore constructed, it

has been the practice to connect the shoulder straps or suspenders to an arm, lever or other motion communicating connection which is fastened, usually in a rigid manner, to the lower leg section in the immediate region of the upper knee end of the latter. As a result, but a short leverage action on the limb is provided, requiring some considerable pull on the shoulder straps or suspenders in order to flex or swing said lower limb section forwardly. This makes, also, the lower leg sec tion but slowly responsive to the pull of the shoulder straps or suspenders, so that the flex ing and knee locking actions are not always suifioiently rapid for a proper walking movement or to prevent a fall.

One object of my invention is to provide means giving a working thrust upon the lower portion of the limb for the flexing action, thereby enabling the wearer to walk with less 39 exertion and fatigue, and which will be rapidly responsive to the pull of the shoulder straps or suspenders to secure the required flexing and knee locking actions for proper slow or fast walking actions so as to avoid slowness of motion liable to cause stumbling or falls.

A further object of the invention is to provide a construction of means for securing these results in a simple manner, so that a to superior type of limb may be produced at low cost.

A still further object of the invention is to provide means of the character described in which that part of the means connected with the lower leg section is wholly enclosed therein, leaving the outer surface of said section free of parts or projections liable to interfere with or to give an undesirable appearance to the garments of the wearer.

The invention consists of the features of Serial No. 213,351.

construction, combination and arrangement of parts, hereinafter fully described and claimed, reference being had to the accompanying drawing, in which Figure 1 is a rear elevation of an artificial limb embodying my invention.

Figure 2 is a side elevation of the same, partially in front-to-rear section.

Figure 3 is a view on an enlarged scale of the combined check and motion transmitting or throw lever Figure f is a view showing the link and guide connection at the upper end of the lever.

Figure 5 is a view of the lower end of the lever, partly in section. v

In the leg construction herein disclosed, for example, the leg comprises an upper leg section 1 and a lower leg section 2, said sections being pivotally connected at the knee joint point by a transverse pin or bolt 3. The said leg sections are hollow, and the hollow section 2 receives a motion transmitting de vice in the form of a combined check and throw lever i. llhis lever 4: is preferably of a length to extend from the upper end of the section 2 to a point at or near, or in the region of, the ankle portion of said section 2.

As shown, the lever 4 is in general longitudinally curved, and in general follows the 39 curvature of the rear portion of the leg section 2, and said lever comprises a body portion having at its upper end a short arm 5 and at its lower end a short arm 6. The formation of the lever is such as to provide a contact portion 7 lying above the horizontal center of the leg section 2 opposite the calf portion thereof, and said contact portion 7 is provided with a flexible or resilient bumper 8, preferably of soft rubber, to bear upon the rear of the leg section 2 at the calf portion and serve as a contact member which reduces friction and prevents rattling at that point. From the portion 7 the body portion of the lever and the arm 5'extend on an upward and forward curve, and immediately in rear of the arm 5 the upper end of the lever is provided with an eye or opening 9 receiving the hinge pin or bolt 3, whereby the lever is mounted coaxially with the leg section 2 to connection comprising links 11 carrying a guide roller 12, for connecting the lever with an actuating or pull device 13. This actuating or pull device may comprise the usual shoulder straps or suspenders, operative through a shoulder motion of the wearer for transmitting a leg throw or flexing motion to the lever l. 1 preferably employ a novel construction of the suspenders in which the suspender ends 14 at the front and rear are joined at their lower ends by a single strap connection 15, which connection 15 passes through guide openings 16 in the leg member 1 and is in running or sliding motion with the roller 12, whereby actuating motion may be transmitted through the connection ll to the arm to impart thrust or leg flexing motion to the lever 4.

The lever 4 is hung from the pivot 3 and is preferably otherwise free from fastening connection with the leg section 2, but, if desired, it may be braced in any suitable manner to adapt it to swing always in a true path :lforwardly and rearwardly and to hold it against lateral play or deflection. It will be observed that this lever extends well down into the section 2 from the knee joint and has two points of bearings 76 on the front and rear, respectively, of said leg portion 2, respectively above and below the horizontal center of said leg section. The portion 7 and its bumper 8 provide a reliable and efficient knee check or knee stop, while the portion 6 with its bumper provides a pressure means or member for transmitting the working thrust of the lever to the leg section 2 for the forward swinging movement or flexing action thereof. This point of pressure being upon the lower portion of the limb, below its hori- Zontal center, provides for the application of the applied power at a point where the least amount of effort is required to impart swinging motion to the leg section 2. By this means a pull upon the pulldevi-ce 18 is greatly reduced over prior construction in which the thrust is transmitted to the upper portion of the lower leg section of the limb, so that the user may operate the limb with much less effort and fatigue. By this means, also, a quicker and smoother flexing movement of the limb section 2 is obtained, causing the leg section2 to move forwardrapidly and lock thus preventing the user from stumbling or falling. Furthermore, greater simplicity of construction is secured, as the number of parts is considerably reduced overthose commonly used, thus lightening the weight of the leg and making it easier to assemble or repair, so that it may be manufactured and maintained in working order at much less cost than similar limbs of ordinary construc tion. By the described construction of the suspenders with the single engaging strap contacting with the pulley 12, the number of parts in this particular is also reduced over conventional constructions, with resulting advantages.

While a certain and particular embodiment of the invention is herein shown and described in detail, it is to be understood that numerous changes in the construction may be made, and,parts varied or omitted, without departing from the spirit of the invent-ion as defined bythe appended claims.

Having thus fully described my invention, I claim I 1. An artificial limb comprising upper and lower leg sections, a pin or bolt pivotally connecting said leg sections at the knee, a lever pivotally mounted at its upper end on said pin or bolt and having an upper arm disposed in the upper leg section and a lower arm disposed wholly in the lower leg section, said lower arm being longitudinally curved to conform substantially to the rear portion of said lower leg section and arranged adjacent thereto ,but spaced therefrom, said lower arm terminating at its lower end adjacent to the ankle portion of the lower leg section and having free end portion loosely engaging said ankle portion of the lower leg section at the front thereof, an abutment upon said lower arm ofthe lever slidably bearing upon the rear wall of the lowerleg section in the region of the calf. portion thereof, and a pull device connected with the short arm of the lever.

2. An artificial limb comprising upper and lowerleg sections, a pin orbolt pivotally connecting s'aid leg sections. at the knee, a lever pivotally mounted atits upper end on said pin or bolt andhaving an upper, arm disposed in. the upper leg-section and a lower arm wholly disposed in the lower leg section, said lower arm being longitudinally curved to conform substantially tothe rear portion of said lower v leg section and arranged adjacent thereto but spaced therefrom, said lower arm terminating at its lower end adjacent to the ankle portion of the lower leg section and having a forwardly projecting member loosely ing said ankle port-ion at the front thereof, a cushioned abutment carried by the lower arm of the lever and slidably engaging the rear wall of the lower leg section in the region of the calf portion thereof, and a pull device connected with the short arm of the lever.

In testimony whereof I affix my signature.

EMMETT BLEVENS. 

